Rape-seed production increased over the last years for industrial purposes such as production of diester. Small plants were set up both for oil extraction from the seed and oil processing. The oil is extracted by pressure so that the ether extract content of rape-seed meal is quite high at about 8%.

The study was designed to compare the effects of different incorporation rates of rape-seed meal in a fattening diet on food intakes and digestibility of the diet.

A total of eight bulls of the Belgian Blue breed-dual purpose type-were used in two 4x4 latin squares design. They were kept in metabolism stalls. There were 4 differents diets (table 1). The control diet was made of sugar-beet pulp, cereals, middlings, soja-bean meal, linseed meal, molasses and mineral mixture. In the three other diets, one third, two thirds and three thirds of the amount of protein from soja-bean meal and linseed meal were substituted by protein from the rape-seed meal. When offered to the bulls, the concentrate was mixed in a mixer trailler with straw at a rate of 90% concentrate and 10% straw. Food intakes were close to ad libitum by daily adjustments. Each period of the latin square lasted for six weeks on the end of which apparent digestibility was measured by total collection of the feces